An issue was discovered in stb stb_image.h 2.27. The PNM loader incorrectly interpreted 16-bit PGM files as 8-bit when converting to RGBA, leading to a buffer overflow when later reinterpreting the result as a 16-bit buffer. An attacker could potentially have crashed a service using stb_image, or read up to 1024 bytes of non-consecutive heap data without control over the read location.

An issue was discovered in stb stb_image.h 1.33 through 2.27. The HDR loader parsed truncated end-of-file RLE scanlines as an infinite sequence of zero-length runs. An attacker could potentially have caused denial of service in applications using stb_image by submitting crafted HDR files.

stb_image.h (aka the stb image loader) 2.23, as used in libsixel and other products, has an assertion failure in stbi__shiftsigned.

stb_image.h (aka the stb image loader) 2.23, as used in libsixel and other products, has a heap-based buffer over-read in stbi__load_main.

stb stb_image.h 2.19, as used in catimg, Emscripten, and other products, has a heap-based buffer overflow in the stbi__out_gif_code function.